I'm training traditional ju-jitsu, but there are a lot of similarities with BJJ. Anyhow, my first class consisted of learning the basic breakfalls, the major hip throw, the Americana (or entangled arm lock), the scarfhold, escaping the mount (Upa), and I forget what else. Plus, the standard 15 minutes of sparring at the end of class.
I've been training for about 3 months now, and those first few months are hard! You really have to learn to think on your feet, take the abuse, learn to conserve your energy, etc. It does get easier, but you get really sore the first few months of it. Then, your body toughens up and you can take (and dish out) more punishment. I submitted my first yellow belt (rough equivalent of BJJ blue belt, as far as I can tell) last week, but you have to get used to spending your time on your back and learning the escapes.
My dojo has a pretty high attrition rate, because the stuff is rough and some people either can't or won't want to handle it. Stick it out, and you'll do fine. Good luck.